Billets-doux (pl)
definition: of Billet-doux

Billets-doux is a 12 letter word that begins with a B and ends in an X

Conservatrix (n.)
definition: A woman who preserves from loss
Injury etc.
Conservatrix is a 12 letter word that begins with a C and ends in an X

Drudging box
definition: See Dredging box.

Drudging box is a 12 letter word that begins with a D and ends in an X

Glossanthrax (n.)
definition: A disease of horses and cattle accompanied by carbuncles in the mouth and on the tongue.

Glossanthrax is a 12 letter word that begins with a G and ends in an X

Odontopteryx (n.)
definition: An extinct Eocene bird having the jaws strongly serrated
Or dentated but destitute of true teeth. It was found near London.
Odontopteryx is a 12 letter word that begins with an O and ends in an X

Plano-convex (a.)
definition: Plane or flat on one side
And convex on the other; as a plano-convex lens. See Convex and Lens.
Plano-convex is a 12 letter word that begins with a P and ends in an X

Pneumothorax (n.)
definition: A condition in which air or other gas is present in the cavity of the chest; -- called also pneumatothorax.

Pneumothorax is a 12 letter word that begins with a P and ends in an X

Streptothrix (n.)
definition: A genus of bacilli occurring of the form of long
Smooth and apparently branched threads either straight or twisted.
Streptothrix is a 12 letter word that begins with an S and ends in an X

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